1. Field of the Invention
This invention relates to an optical system for shaping the diverging beam from the exit surface of a semiconductor laser.
2. Description of the Prior Art
In general, the beam emitted from a semiconductor laser known as the diode laser or the injection laser has different angles of divergence in directions orthogonal to each other. There are also semiconductor lasers which emit beams having different source points of divergence in directions orthogonal to each other. It is impossible to treat such a semiconductor laser beam by the use of a rotation symmetry lens, namely, a lens having equal focal lengths in directions orthogonal to each other, so that the beam may be collimated or made into a circular spot light.